The problems we encountered were due more to the extent of improvements, optimizations and fixes. We're touching a lot of legacy code and changes to it tend to blow up at the worst of times, like when launching the expansion ... or two days later... at 5 in the morning... while you're having sex. (Well, I was dreaming about it. Don't ask.) Since then, we've been deploying server-side updates about two or three times a week and we're still investigating performance issues related to bugs.